Knock over bit for knitting machines



Dec- 33- E. J. WELFFENS 1,939,092

KNOCK-OVER BIT FOR KNITTING MACHINES Filed Jan. 6, 1931 /N VE N TOR 3 6U f w: Jews I A770 NE S Patented Dec. 12, 1933 KNooK oven BIT FOR KNITTING MACHINES Emile John Welffens, Fallowfield, England, as-

signor to Harcowo Societe Anonyme, Geneva,

Switzerland, a company of Switzerland Application January 6, 1931, Serial No. 506,859,

and in Great Britain January .28, 1930 7 Claims. (Cl. 66-109) The present invention relates to improvements .in orrelating to knock-over bits for knitting machines, particularly but 'not exclusivel-y for circular knitting machines. r 6 One of the objects of the resent invention is to provide an improved form of knock-over bit which does, not require the provision of a special slot forits location on themachine.

A further object of the invention is to provide 10 a-knock-over bit which is capable not only of serving the usual purpose ofassisting in drawing the loops during the process of knitting,-but also of serving as a guide and a separator for a Warp thread to be incorporated in the knitted fabric, as a means for assisting to lay a weft thread likewise to be incorporated in the fabric alternately above and below the knitting needles, as a means for retaining the, knitted fabric in position when used in a horizontal needledbed knitting internally or externally and as a means. for assisting the knitting thread into engagement withthe needle hook. 1

According to the present invention I provide a knock-over bit. for knitting machines having a relatively thick base or tail portion adapted to engage on each side with adjacent jacks when in the machine and a working head portion reduced in thickness so as to give the necessary clearance for the needles.

The working head of the knock-over bit is preferably of a depth somewhat greater than is usual and is preferably specially shaped so that it can perform the several functions enumerated above. A slot is provided for guiding and retaining the warp thread. The knock-over bit may be constructed from a single piece of metal or it may be built up of several pieces which may be secured together in any desired manner.

In order that the invention may be well understood, a preferred embodiment thereof will be described by way of example only and with reference to the accompanying drawing in which:

Figures 1, 2 and 3 are side elevations of portions of a built up knock-over bit embodying the present invention.

Figure 4 is an end elevation of the knock-over bit.

Referring to the drawing, the bit is a built up structure consisting of five laminae. A'central lamina or distance piece 2 extends throughout the whole length of the bit and two laminae 1 of steel which are shaped at their upper portions to form the working head 4 of the bit are disposed one on each side of the central distance piece 2. On either side of the composite structure made up of these three pieces are two outer laminae or distance pieces 3, which do not extend all the way to the top of the bit but terminate short of the working head 4 so as to allow clearance for the needles between the working heads of consecutive bits. The three distance pieces 2 and 3, 3 may be made of any suitable material such for example as steel or hard brass. The five ,pieces which together constitute the knock-over bit aresecured togetherin any suitable manner such for example as by: riveting, welding, soldering or sweating. In. the embodiment illustrated holesor slots 5 and 6 are provided in the distance pieces 2 and 3 respectively. These holes or slots are filled with solder and then the five pieces are put together and heated whilst being pressed together, so that the solder flows and effectively binds the pieces together. The tail portion '7 .of the extension slopes in a gradual convex curve backwards and downwards towards the front vertical edge 12 of the part 8. Where the lower edge ll joins the front vertical edge 12 is a recess or slot 13. It will be seen that when a weft thread or a knitting thread is caught by a needle hook it is forced to descend and follows the top sloping edge of the extension 9, passes round the ex- 0 tremity 10, follows the lower edge 11 and finally enters the recess or slot 13, which retains the thread below the needles as and when necessary. The recess or slot 13 lies slightly below the top of the fabric being knitted and therefore assists 9, in retaining the fabric in position when the needles are moved forward for the next stitch.

The bits may be secured to the needle bed in any desired manner such as by means of clamping plates which grip the tails of the bits either directly or through suitably interposed packing. The clamping plates are preferably shaped and arranged so that as they are tightened they tend to force the tails of the bits into engagement with two locating surfaces at right angles to one another. In the embodiment illustrated a step 14 is formed in the rear edge of the bit to assist positioning. Each clamping plate is adapted to retain a number of bits in position the'number r varying according to the gauge of the machine and therefore the width of the bits.

Whilst in the foregoing a preferred embodiment of the invention has been described it is to be head having a forward extension and a recess at the base of said extension for retaining. the threads below the needles after a stitch, and two outer laminae which terminate below the working head, said laminae being secured together to form a unit.

2. A knock-over bit for knitting machines comprising two laminae spaced apart by a central lamina and shaped at the top to form a working head having a forward extension and a recess at the base of said extension for retaining the threads below the needles after a stitch, and two outer lamina which terminate belowthe working head, a step being provided in the rear edge of the jack to assist in positioning in the machine, all of said lamina being united into a unitary structure.

3. A composite unitary knock-over bit for knitting machines comprising a plurality of lamina permanently fixed together ,of which the lamina on one side does not extend throughout the full length of the bits but terminates short of the head portion thereof so that a relatively thick tail portion is provided adapted to engage on each side with adjacent bits when in the machine, the head'portion being formed for retaining a warp thread mid-way between two adjacent needles when the bit is in the machine.

4. A composite unitary knock-over bit for knitting machines comprising a plurality of lamina secured together of which the lamina on both sides do not extend throughout the full length of 'the knock-over bit but terminate short of the for retaining the threads below the needles after a stitch and two outer lamina which terminate below the working head, the head portion being shaped for retaining a warp thread midway between two adjacent needles when the bit is in the machine. I

'6. A composite knock-over bit for knitting machines comprising two lamina spaced apart by a. central lamina and shaped at the top to form a working head having a forward extension and a recess at the base ofsaid'extension for retaining the threads below the needles after a stitch and two outer' lamina which terminate below the working head a step being provided in the rear of the jack to assist in positioning in the machine and the working head being shaped for retaining a warp thread midway between two adjacent needles when the bit is in the machine,

'said lamina being secured together into a unitary structure.

'7. A composite knock-over bit for knitting machinescomprising two lamina spaced apart by a centrallamina and shaped at the top to form a working head having a forward extension and a recess at'the base of said extension for'retaining the threads below the needles after a stitch and two outer lamina which terminate below the working head and serve as active supports for the sliding needles when the bit is in the machine,

said lamina being rigidly united into a unitary structure.

"EMILE JOHN WELFFENS. 

